CHAPTER 5 Section 5 4Scale Drawing Book cover

CHAPTER 5 Section 5. 4–Scale Drawing Book cover image by i. Stock. com/Mc. Kevin Shaughnessy

Section 5. 4 Scale Drawing A scale drawing is a drawing such that all the ratios of lengths in the drawing to the actual lengths are equal. p. 214

Section 5. 4 Scale The scale is the ratio of the length of a drawing to the actual length of the item drawn. p. 214

Section 5. 4 Scales can be written in two different ways. 1 in. 4 ft. 1 in. : 4 ft. p. 214

Section 5. 4 p. 214

Section 5. 4 Example 1 Find the approximate distance from Pittsburgh to Philadelphia. The scale is 1 in. : 50 mi. The distance on the map is about 5 in. 1 • n = 50 • 5 1 5 = 50 n n = 250 mi. p. 215

Section 5. 4 Skill Check 1 Using the map of Pennsylvania, about how far is it between the cities listed? 1. Harrisburg to Altoona 2. Erie to Chambersburg 3. Gettysburg to Wilkes-Barre p. 215

Section 5. 4 Skill Check 1 4. The scale on a map is 1 cm : 3 km. Find the distance represented by 6. 4 cm. 5. A scale drawing of a bridge uses the scale 3 cm : 10 m. If the bridge is 7 cm on the drawing, what is the actual length (round to tenths)? p. 215

Section 5. 4 Example 2 The dimensions of a house are 48 ft. by 42 ft. The dimensions on the floor plan are 8 in. by 7 in. What scale is used for the drawing? Length in the drawing to the actual length: 8÷ 8 8 in. 1 in. = = 48 ft. 48 ÷ 8 6 ft. p. 216

Section 5. 4 Example 3 If a 14 ft. long table is 4 in. long on the drawing, what scale is used? 4÷ 4 4 in. 1 in. = = 14 ft. 3. 5 ft. 14 ÷ 4 p. 216

Section 5. 4 Skill Check 1 Find the scale used for the following. 1. A 35 km distance is 5 cm on a map. 2. A model of a 64 ft. coal car is 8 in. long. 3. A 12 ft. wide bedroom is drawn to be ¾ in. on the sketch. p. 216